102 MISSOURI AGRICULTURAL REPORT. 



Of all the bread plants adapted to our soil and climate, none yields 

 so large a quantity of potential food to the acre as Indian corn. A 

 yield of loo bushels to the acre,\vhich is quite within easy possibility, 

 means a total product, exclusive of roots and stubble, of 6 to 7 tons of 

 air-dry matter all of which may be utilized as food by man or beast. 

 A corresponding- crop of wheat would be 40 bushels to the acre, weigh- 

 ing, with its straw, 3 1-2 to 4 tons. 100 bushels of corn with its cobs 

 and stover, will carry from the soil about 160 pounds of nitrogen ; 40 

 bushels of wheat, with its straw half as much. The loo-bushel corn 

 crop will require about 2 1-2 times as much phosphorus and three times 

 as much potassium as the 40 bushel wheat crop. 



The corn crop grows during the hot summer months, when the 

 nitrifying bacteria are most actively at work ; wheat makes its growth 

 largely during the cooler weather of the fall and spring. Not only this, 

 but to stimulate the work of nitrification in our corn fields by stirring 

 the soil at intervals during the season, distributing the organisms 

 throughout the soil and keeping them well supplied with oxygen, with- 

 out which that work would cease. 



At the Ohio Experiment Station an acre each of corn, oats and 

 wheat has been grown continuously on the same land for 12 years. 

 These acres lie side by side, on land uniform in character, and of low 

 fertility at the beginning of the test. Considering the grain alone, and 

 comparing the yields by 6-year periods, the average unfertilized yield of 

 corn has fallen from 26 bushels per acre for the first periol, to 14 2-5 

 bushels for the second, a loss of 45 per cent; that of oats, from- 28 

 bushels for the first period to 23 1-3 bushels for the second, a loss of 

 17 per cent, and that of wheat from 9 bushels for the first period to 7 3-5 

 bushels for the second, a loss of 15 per cent. The rate of decrease in 

 yield, therefore, has been three times as great for corn as for wheat, and 

 nearly three times as great for corn as for oats. 



Professor Harry Snyder of the Minnesota Experiment Station has 

 shown that the waste of soil nitrogen may be indefinitely greater than 

 the quantity utilized. For twelve years in succesion he grew wheat on 

 the same land. Tie determined the nitrogen in the soil at the beginning 

 and end of this period, and found that there had been a reduction of more 

 than 2,000 pounds per acre, or 26 per cent of the quantity found in the 

 soil at the beginning of the test. Of this loss, only 450 pounds could be 

 acounted for in the crops taken off the land, showing that nearly 1,600 

 pounds had been lost mainly through decay of the humus and liberation 

 of the nitrogen. 



